Please help break down this question

A credit card company uses the average daily balance method to calculate its finance charges.What is the finance charge for the month of August (31 days) for this credit card if the average daily balance for August is $233.13?The annual interest rate is 18%.

(Round to the nearest cent.)

July 31 - Balance - $250

August 9 - Charge - $77

August 14 - Payment - $210

August 22 - Charge - $131

August 24 - Charge - $22